Gauthier V J, Mannik M
Department of Medicine, University of Washington, Seattle, WA 98195.
J Immunol. 1990 Nov 15;145(10):3348-52.
Positively charged antibodies mediate enhanced deposition of circulating immune complexes at the glomerular basement membrane. The presented experiments demonstrate that when soluble immune complexes were prepared with a mixture of antibodies containing 10 to 25% cationic antibodies, then noncationic antibodies in the complexes were deposited in mouse glomeruli. One or two cationic antibodies in each immune complex sufficed for deposition of the complexes. Proof for this was obtained by two kinds of experiments. First, the injected immune complexes were prepared in Ag excess from mixtures of radiolabeled noncationic rabbit antibodies to human serum albumin (HSA) and unlabeled cationized rabbit antibodies to HSA, thus permitting the specific quantitation of the deposition of noncationic antibodies in glomeruli because of the presence of cationized antibodies within the same complexes. As a control experiment, immune complexes prepared only with noncationic antibodies resulted in very little deposition in kidneys over the same time period. Second, detection of the localization of the noncationic antibody in deposits in glomeruli by immunofluorescence microscopy was accomplished using immune complexes prepared with mixtures of noncationic goat antibodies to HSA and cationized rabbit antibodies to HSA. Thus, the synthesis of a small population of cationic antibodies during the immune response may lead to the formation of circulating immune complexes with enhanced propensity for deposition in glomeruli in patients with SLE or other immune complex diseases.
带正电荷的抗体介导循环免疫复合物在肾小球基底膜的沉积增强。所展示的实验表明，当用含有10%至25%阳离子抗体的抗体混合物制备可溶性免疫复合物时，复合物中的非阳离子抗体就会沉积在小鼠肾小球中。每个免疫复合物中有一两个阳离子抗体就足以使复合物发生沉积。这一点通过两种实验得到了证实。首先，从放射性标记的抗人血清白蛋白（HSA）的非阳离子兔抗体与未标记的抗HSA阳离子化兔抗体的混合物中，在抗原过量的情况下制备注射用免疫复合物，这样由于同一复合物中存在阳离子化抗体，就可以对肾小球中非阳离子抗体的沉积进行特异性定量。作为对照实验，仅用非阳离子抗体制备的免疫复合物在同一时间段内肾脏中的沉积极少。其次，通过使用抗HSA的非阳离子山羊抗体与抗HSA阳离子化兔抗体的混合物制备免疫复合物，利用免疫荧光显微镜检测肾小球沉积物中非阳离子抗体的定位。因此，在免疫反应过程中少量阳离子抗体的合成可能导致循环免疫复合物的形成，这些复合物在系统性红斑狼疮或其他免疫复合物疾病患者中具有增强的在肾小球沉积的倾向。
